Fluted reflector



Sept 29, 1925. 1,555,410

c. E. GODLEY FLUTED REFLECTOR Original Filed Junel s, 1922 2 Sheets-Sheet 1 N "s-w Sept. '29, 1925. 4 1,555,416

c. E; GODLE'Y FLUTED REFLECTOR Original Filed June 16, 1922 I z Sheets-Sheet '2 Q N "1 t I N VEN TOR.

A TTORNEY.

Patented Sept. 29, 1925.

UNITED STATES PATENT OFFICE.

CHARLES E. GODLEY, OF DETROIT, MICHIGAN, ASSIGNOR TO-EDMUNDS AND JONES CORPORATION, OF DETROIT, MICHIGAN, A CORPORATION OF NEW YORK.

FLUTED REFLECTOR.

Application filed June 16, 1922, Serial No. 568,778. Renewed July 20, 1925.

To all whom it may concern:

Be it known that 1, CHARLES E. GonLEY,

a citizen of the United States, and residing at Detroit, in the county of Wayne and State of Michigan, have invented a new and Improved Fluted Reflector, of which the following is a specification.

This invention relates to the construction of the reflectors of projecting lamps for vehicles of the type shown in my prior applications, Serial No. 559,204 filed May 8th,

1922, and Serial No. 562,065 filed May 19,

1922, and has the same general object, that is, to so divide the reflector into sections that the rays of light will be projected upon aclearly defined limited area and in part concentrated upon a restricted portion of said area.

This present invention again employs a simple substantially parabolic reflector so deformed that different portions thereof will project beams whose cross sections'are similar in shape but different in size, and that a considerable portion of the road in advance of the vehicle will be illuminated to a limited degree while another portion of the roadway a greater distance. ahead of the vehicle will be illuminated by a more concentrated beam.

An ordinary paraboloidal reflector is divided into a series of panels which extend transversely to thedirection in which the beam is to be expanded, each of these panels having its longitudinal medial portion disposed out of the general paraboloidal surface of the reflector, the lateral edges of the panels remaining in this original paraboloidal surface. The depths and widths of these panels and the directions of their curvatures may be varied according to the desired spread of the projected beam, and the relation of the central lines of the panels to the vertical plane passing through the axis of the reflector may be varied according to the direction in which the beam is to be expanded.

The cross-section of any panel on a line radial to the inner edge of the panel is the same as a horizontal cross-section of the same width of a predetermining parabola having the same focal point and focal axis but less focal distance than the reflector, the center of this cross-section of the determim ing parabola being in a line connecting the focal points of the parabola and the center of the said cross-section of the panel. This is true in reflectors the sides of whose panels are all parallel and vertical and in re flectors divided into curved or, irregular panels, so long as the cross-sections of these panels are tilted into the planes in which light is to be spread. If the central lines of the panels of a reflector having a horizontal axis were all in vertical planes, the beams of the reflector would be expanded from circular to elliptical cross-sections with the major axis horizontal. But if the panels are curved slightly toward or away from a vertical plane, the beam is changed in cross section substantially to that of a horizontal rectangle. This is fully explained in my prior applications.

These panels may all be of the same width or of different Widths, the spread of light being determined by the focal length of the determining parabola, varying substantially inversely with such length.

Panels having paraboloidal sections project rays which diverge equally from the axis of the reflector, the rays of each panel covering substantially a predetermined field of light.

In the accompanying drawing, Fig. 1 is a vertical section of a reflector embodying the resent invention on the line 1--1 of Fig. 3. ig. 2 is a diagram illustrating the effect of the light rays projected by the reflector shown in Figs. 1, 3 and 4. Fig. 3 is a front elevation of this reflector. Fig. 4 is a section on the line 4+4 of Fig. 2. Fig. 5 is a vertical section of a modified form of this reflector on the line 5-5 of Fig. 7. Fig. 6 is a diagram illustrating the effect of the light rays projected by the reflector shown in Figs. 5, 7, and 8. Fig. 7 is a front elevation of this modified form of reflector. Fig. 8 is a section on the line 8-8 Fig. 7.

Similar reference characters refer to like parts throughout the several views.

After the blank for the reflector 11, shown in Figs. 1, 3 and 4 has been drawn to paraboloidal shape and polished it is placed between proper dies and its surface is deformed so as to be divided into panels 13 and 14. Those on each side and next to the central aperture 12 of the reflector being narrower than those farther away, although these widths may be reversed.

, Each of these panels is substantially in a vertical plane as shown in Fig. 3, those in each side of the center of the reflector being parallel to each other, but the upper and lower ends of all the panels on each side of the central opening 12, curve toward the central vertical plane of the reflector in order to effect the projection of diffused light toward the corners of the main projected field.

I The method of obtaining the exact transverse curvatures of each of the various panels is shown and described in my said former applications. The lines which represent the bottoms of the scorings are heavier at the middle of Fig. 3 than along the edges in order to indicate that the transverse curvature or convexity of the panels 13 is greater between these heavy lines than outside of this central area.

Fig. 2 represents a field of illumination divided into squares by the horizontal lines 0 to 4 and the vertical lines 0 to 10. A substantially parabolic reflector with a properly focused filament should illuminate a circular area which is about one hundred feet from the lamp and having a diameter equal to two degrees of arc, the center of the are being at the filament of the light bulb. The diagram is divided to represent these degrees of arc. The rays of light projected by the deeply scored panels indicated by thelines 15 will diffuse the light over a rectangle extending between the horizontal lines 0 and 4 and the vertical lines 8 and 8, this area of illumination being substantially rectangular because of the curvature of the upper and lower ends of the panels toward the axial vertical plane of the reflector.

That annular portion of the reflector whichis not so deepely corrugated or that in which the transverse convexity of the panels is relatively small will not diffuse the rays to such an extent, the field illumination being found to extend between the vertical lines 3 and measuring about two spaces up and down. This area of illumination is superimposed on the larger area projected by the less deeply corrugated or scored panel portions, that is, the rays projected by the outer annular portion of the reflector are received on a portion of the field which also receives rays from the central portion of the reflector so that this second and limited portion of the illuminated field becomes much brighter than the remainder of the field.

WVhen this reflector is used in the headlight of an automobile it is very desirable that that portion of the roadway farthest from the vehicle shall receive as much light as possible while the roadway between this orightly illuminated portion and the vehicle shall be lighted up sufliciently to permit the driver to- Watch the roadway. The outer annular portion of the reflector is therefore tilted up relative to the central portion, so that its focal axis 16 will form a slight angle relative to the focal axis 17 of the inner more deeply corrugated portion. The lines 18 and 19, Figs. 1 and 2, from the tops of the outer and inner areas meet at the intersection of the lines 0 of the diagram, while the line 20 extends from the bottom of the deeply corrugated area to the intersection of the vertical line 0 with horizontal line 4 and the line 21 extends from the bottom of the reflector to horizontal line .2. These lines therefore indicate the vertical heights of the illuminated areas.

Figs. 5 to 8 inclusive show a similar reflector 23 provided with narrow panels 24 adiacent the central vertical plane of the reflector and wider panels 25 outside of these narrow panels. The heavy lines 26 in Figs. 5, 7, and 8 indicate deeper scoring between the panels and therefore greater convexity of the panels in cross-section between these deeper scorings. The central portion of the reflector which is not so deeply corrugated as the outer portion will not diffuse the rays of light to such an extent as the outer portion, and the field of illumination will not. be as great either horizontally or vertically. The shallow and deeper corrugations may be said to be divided by a plane 27-27 indicated in Fig. 5. The field of illumina: tion indicated in Fig. 6 is substantially the same as in Fig. 2, and this diagram, Fig. 6, again presents a highly illuminated portion of the field extending between horizontal lines 0 and 2, and between upright lines 4, the illuminating beam for this area being projected by the central portion of the refiector. T he beams from the annular deeply corrugated portion of the reflector illuminate the area between horizontal lines 0 and 4 and vertical lines 9 to a very much less degree.

In the reflector shown in Figs. 5, 7, and 8. the central portion of the reflector is tilted up to a slight extent so that the restricted areas illuminated thereby will be above the center of the larger area illuminated by the deeply corrugated annular portion of the reflector. The focal axis of the central portion is indicated by the line 28 while that of the outer portion by the line 29. The upper and lower boundaries of. the restricted beam are indicated by the lines a. while those of the diffused beam are indicated by the lines 7) in Fig. 5. The relative positions of these strongly and moderately illuminated areas may be varied as desired by changing the angle between the axes 16 and 17 and between the axes 28 and 29 in the two embodiments of this invention.

It is obvious that the various features of this invention may be embodied in a variety of lamps and that reflectors may be constructed according to my invention to produce Widely differing degrees of illumination of different areas of the projected field, and that the widths of the panels, the depths of the corrugations and the relative areas of the reflecting surface which have deep and shallow corrugations respectively may be varied by those skilled in this art without departing from the spirit of my invention as set forth in the following claims.

I claim:

1. A paraboloidal reflector composed of a group of panels on each side of the center of the reflector, the panels having parallel sides and the panels of each group being parallel to each other, each panel being transversely convex toward the general focus of the reflector, the adjacent edges of the inner panels of the two groups being curved apart at the center of the reflector, the inner panels being narrower than the outer, the corrugations of a central area of the reflector being of different depth in proportion to the width of the corrugations than the corrugations of the surrounding area.

I 2. A paraboloidal reflector composed of a group of panels on each side of the center of-the reflector, each panel being transverse- 1y convex toward the general focus of the reflector, the adjacent edges of the inner panels being curved apart at the center of the reflector, the inner panels being narrower than the outer, the corrugations of a central area of the reflector being of different depth in proportion to the width of the corrugations than the corrugations of the surrounding area.

3; A paraboloidal reflector composed of a group of panels on each side of the center of the reflector, each panel being transversely convex toward the general focus of the reflector, the inner panels being narrower than the outer, the corrugations of a central area of the reflector being of different depth in proportionto the width of the corrugations than the corrugations of' the surrounding area.

4. A paraboloidal reflector corrugated to form panels on each side of the center of the reflector, each panel being transversely convex toward the general focus of the reflector, the inner panels being narrower than the outer, the corrugations of the central area of the reflector being of different depth in proportion to the width of the corrugations than the corrugations of the surrounding area.

5. A paraboloidal reflector corrugated to form panels on each side of the center of the reflector, the panels having parallel sides and the panel of each group being parallel to each other, each panel being transversely convex toward the general focus of the reflector, the adjacent edges of the inner panels of the two groups being curved apart at the center of the reflector, the corrugations of the central area of the reflector being of different depth in proportion to the width of the corrugations than the corrugations of the surrounding area.

6. A paraboloidal reflector corrugated to form panels on each side of the center of the reflector, each panel being transversely convex toward the general focus of the reflector, the corrugations of the central area of the reflector being of different depth in proportion to width than the corrugations of the surrounding area.

7. A paraboloidal reflector corrugated to form panels on each side of the center of the reflector, each panel being transversely convex toward the general focus of the reflector, the corrugations of the central area of the reflector being of different depth in proportion to width than the corrugations of the surrounding area, the general focal axis of the inner area being at an angle to the general focal axis oLthe outer area, both focal axes being in the same vertical plane.

8. A paraboloidal reflector corrugated to form panels on each side of the center of the reflector, each panel being transversely convex toward the general focus of the reflector, the corrugations of the central area of the reflector being deeper in proportion to their width than the corrugations of the surrounding area.

9. A paraboloidal reflector corrugated to form panels on each side of the reflector, each panel being transversely convex toward the general focus of the reflector, the corrugations'of the central area of the reflector being deeper in proportion to their width than the corrugations of the surrounding area, the general focal axis of the inner area being at an angle to the general focal axis of the outer area.

10. A paraboloidal reflector corrugated to form panels on each side of the center of thereflector, the panels having parallel sides and the panels of each group being parallel to each other, the adjacent edges of the in-. ner panels of the two groups being curved apart at the center of the reflector, the corrugations of the central area of the reflector being of greater depth in proportion to the width of the corrugations than the corrugations of the surrounding area, the general focal axis of the inner area bein at an angle to the general focal axis 0 the outer area. a

11. A reflector having a substantially paraboloidal reflecting surface formed into panels, all extending generally in the saine direction with one medial plane of the iteflector, each panel being transversely convex toward the general focus of the reflector, the/z:

central area being narrower and; of greater depth in proportion to the Width of the corrugations than the corrugations of the surrounding area, and the general focal axis of the inner area being at an angle to the general focal axis of the outer area so that said areas "will project beams of light of substantially rectangular cross section and having substantially the same upper plane, the area of the beam projected by the panels of the outer areas being smaller than that projected by the panels of the inner area onthe same plane.

CHARLES E. GODLEY. 

